put past

blast from the past

Something or someone that a person has not seen for a long time that evokes nostalgic feelings.

ghost from one's past

Something unpleasant from one's past that "haunts" them (makes them feel uneasy) to the present day.

live in the past

To dwell on and ruminate about past events.

not to put too fine a point on it

Used to apologize for a possibly impolite statement one is making; to put it bluntly; to express it in plain terms.

pea-time is past

Something is ruined or gone beyond recall.

put a band-aid on a bullet wound

To inadequately treat a serious situation.

put a blanket over

Make (something) seem less serious.

put a bug in someone's ear

To make a small suggestion or give a hint that causes the listener to act.